The present invention relates, in general, to surgery and, in particular, to a new and useful surgical transection or cutting device for fastening and transecting tissue.
During many surgical procedures, it is common to use a tissue fastening device, such as a linear cutter, for stapling and transecting tissue in order to resect the tissue and achieve hemostasis by placing a plurality of laterally spaced rows of staples on opposite sides of a tissue cut or tissue transection line. The tissue transection line is placed in the tissue by advancing a cutting blade through the tissue simultaneously with the firing of the staples. For those surgical procedures which require the transection of tissue with a linear cutter, it is important that the cutting blade of the linear cutter have a quality cutting edge for penetrating and cutting the various types of tissue that are normally encountered during a procedure. Moreover, it is also important to have a cutting blade with an edge that can cut through varying thicknesses of tissue as well as have the ability to cut through other structures which may be encountered while cutting the tissue. Thus, when using a linear cutter, it is of great importance that the cutting blade remain sharp and resist dulling over repeated firings of the device.
As mentioned above, there are various surgical procedures which require a surgical transection or cutting device, such as a linear cutter. Some of these procedures not only utilize a linear cutter but also include a buttress material to be used in conjunction with the linear cutter. A buttress material, sometimes referred to as a pledget material, is placed between the staples and the tissue in an effort to achieve better hemostasis and/or pneumostasis. U.S. Pat. No. 5,263,629 (Trumbull et al.), U.S. Pat. No. 5,397,324 (Carroll et al.), U.S. Pat. No. 5,542,549 (McKean et al.) and U.S. Pat. No. 5,549,628 (Cooper et al.) disclose typical surgical instruments used in conjunction with buttress material for many different surgical procedures.
A lung volume reduction procedure is one of these procedures in which a section of lung tissue is removed with a linear cutter. During a lung volume reduction procedure, it is common to resect portions of a patients lung in order to remove diseased lung tissue from healthy lung tissue. This procedure usually requires multiple firings from the linear cutter or other types of surgical transection instruments. As a result of these multiple firings, it is a common occurrence for the staple lines which have been placed in the lung tissue to be crossed with the newly fired lines. The crossing of staple lines occurs in an effort to resect only those sections of diseased lung tissue that are necessary in an effort to preserve the integrity of the remaining lung tissue. Accordingly, when crossing staple lines, the cutting blade of the linear cutter often encounters the staples in the tissue which have been previously placed from previous firings. When encountering a previously placed staple, the surgeon often encounters difficulty in completing the firing stroke due to increased forces to fire as a result of the staple being located directly in the path of the cutting blade. Moreover, upon encountering a previously placed staple or any other obstruction located in the cutting path of the cutting blade, the cutting blade is usually dulled because the staple will engage the cutting edge of the cutting blade and will travel along the length of the edge. As a result of the staple dulling the blade edge, the surgeon will find it extremely difficult to transect tissue on subsequent firings for those linear cutters which have cutting blades prescribed for multiple firings.
For surgical linear cutter devices, such as those mentioned above, the cutting edge of the cutting blade has a linear and uniform configuration. However, one known prior art reference, U.S. Pat. No. 5,554,164 (Wilson et al.), discloses a linear cutter device having a non-linear cutting edge for preventing uncut tissue, otherwise known as a wisp, from sliding between the cutting blade and the upper finger of the linear cutter. The blade edge design has a single tip at opposite ends of the blade edge which is directed to preventing the wisping of the tissue. Although this non-linear blade configuration may avoid the formation of wisps within the surgical cutter, one major drawback to the blade edge design is that it is ineffective in preventing dulling of the cutting edge upon encountering an object, such as a staple, located in the cutting path of the cutting blade. Accordingly, upon encountering a staple in the cutting path, the staple is not prevented from moving along a substantial portion of the blade edge. Thus, a substantial portion of the cutting edge will be dulled and completion of the cutting stroke will be extremely difficult. Furthermore, since the cutting blade is disposed of along with the cartridge after the initial firing, subsequent usages of the dulled edge is not an issue.
Presently, one known way which is utilized to provide a quality cutting edge on a surgical linear cutter is to utilize a disposable cartridge which includes a cutting blade such that after each firing of the linear cutter, the expended cartridge and the used blade are disposed of and a new cartridge containing a new cutting blade is loaded in the linear cutter and utilized in the next firing of the instrument. A major drawback to this type of cartridge design is that there is a substantial cost associated with a cartridge that includes a one time use disposable cutting blade that is disposed of along with the spent cartridge upon one firing of the linear cutter.
Presently, there is no known surgical transection device or tissue fastening device, such as a linear cutter, that can ensure an effective cutting edge upon encountering a previously fired staple or other object located in tissue along its initial cutting stroke as well as subsequent usages.